State Gun Policy and Cross-State Externalities: Evidence from Crime Gun Tracing
利用犯罪枪支追踪数据，研究发现枪支从宽松法律州流向严格法律州，且邻近州的宽松法律会增加本州的非法持枪率，揭示了跨州枪支政策的外部性。
This paper provides a theoretical and empirical analysis of cross-state externalities associated with gun regulations that impact gun trafficking. Using tracing data, which identify the source state for crime guns recovered in destination states, we find that firearms tend to flow from states with weak laws to states with strict laws, satisfying a key theoretical condition for the existence of externalities. We also find that gun flows are more significant between nearby states, suggesting that externalities are spatial in nature. Finally, we present evidence that criminal possession of guns is higher in states exposed to weak laws in nearby states.